Cyst/lump

I recently found a small pinky nail sized raised cyst like lump under my 14 year old female cats arm on her chest. I took her to the vet and they could not say for sure what it was without a costly biopsy or surgical removal.

I'm hoping its a harmless cyst and said I would prefer to watch it and see.
The vet sent me home with Animax Cream (anti-inflammatory) but again they could not say if this could cause a problem by using it.

Has anyones cat ever had a cyst? I'm hoping thats all it is and not cancer.
Also has anyone used Animax on a cyst?

I'm not sure what to look for to know if this raised lump is good or bad.

Thanks for your help!

I urge you to have a veterinary dermatologist take a look at this and then please, follow the specialist's advice.

Info
http://www.peteducation.com/article....1+2141&aid=204

To find a dermatologist
http://www.acvd.org/

Cynthia had a cyst, but the vet put a needle in it to do a biopsy and it (the cyst) broke. That's how we knew it was a cyst. I would have the biopsy if it were me.